You can include OR uppercase keyword:e.g. dna OR rna looks for keywords dna or rna.

You can include - prefix or NOT uppercase keyword to define keywords that should not be included:e.g. dna OR rna NOT protein (alternatively: dna OR rna -protein) will look for links with keywords DNA or RNA, but not protein

PathExpress

PathExpress is a tool developed to interpret gene expression data obtained from microarray experiments by identifying and visualizing the most relevant metabolic pathways associated with a subset of genes (e.g. differentially expressed genes). Enzyme Neighborhood (a sub-network of linked enzymes with a limited path length) allows identification of the most relevant sub-network affected in a gene expression experiment.